Allocating capacity of a network connection to data streams based on type

ABSTRACT

A user of a communication network may have specific requirements for its critical data streams. The user may require dedicated channel capacity for its critical application. A dedicated channel may be separate from a common channel carrying non-critical data of the user. The user may create policies for assigning channel capacities to its critical data streams based on various criteria. The user may also create policies on sharing the dedicated channel capacity among its different critical data streams.

BACKGROUND

Field

This field is generally related to communication networks.

Related Art

A communication network may, for example, provide a network connectionthat allows data to be transferred between two geographically remotelocations. A network connection may allow different types of datastreams to reach their respective destinations.

The network connection may have a particular bandwidth reserved for aparticular user. In other words, no other user of the network can haveaccess to the bandwidth reserved for a particular user on a dedicatedconnection. Reserving may involve associating a particular bandwidthwith a user. While still reserving bandwidth, a network may beoversubscribed, meaning that if all users were using all theirassociated bandwidth, the network would have insufficient capacity. Thebandwidth assigned to a connection may be shared among different typesof applications and data streams using the connection.

Different types of data streams may have different capacity needs. Auser may generate different data streams and have different requirementsfor transmission of each type of data stream. For example, a data streammay have certain capacity or latency requirements. A user's requirementsfor the data stream may also vary depending on the time. To deal withchanging requirements over time, some communication networks allow auser to change a connection's capacity during a specified time period inthe future.

While adjusting connection capacity may accommodate some flexibility,having a shared channel may result in unnecessary competition amongdifferent traffic streams.

BRIEF SUMMARY

In an embodiment a computer-implemented method transmits data from asource to a destination through a plurality of interconnected forwardingdevices. The method includes receiving at a forwarding device, on acommon channel from the source to the forwarding device, a first packetin a first data stream. The common channel may have a common capacity.In response to receiving the first packet, the first packet is forwardedon the common channel from the forwarding device to the destination.Also it is determined whether the first data stream is a critical datastream, based on information about the first packet in the first datastream. When the first stream is determined not to be critical in, theforwarding device is configured to forward a second packet of the firstdata stream on the common channel from the forwarding device to thedestination. When the first data stream is determined to be critical,the forwarding device is configured to forward a second packet of thefirst data stream on a first channel from the forwarding device to thedestination. The first channel has a first capacity and the firstchannel is different from the common channel.

System and computer program product embodiments: are also disclosed.

Further embodiments, features, and advantages of the invention, as wellas the structure and operation of the various embodiments, are describedin detail below with reference to accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated herein and form partof the specification, illustrate the present disclosure and, togetherwith the description, further serve to explain the principles of thedisclosure and to enable a person skilled in the relevant art to makeand use the disclosure.

FIG. 1A is a diagram that illustrates a system for providing a networkconnection for a user.

FIG. 1B is a diagram that illustrates a system for providing a networkconnection for a user.

FIG. 2 is a diagram that illustrates modules of a forwarding device anda policing device.

FIG. 3 is a diagram that illustrates different channels that may beassigned to a user data streams.

FIG. 4 is a flowchart that illustrates a method for assigning a channelto a user data stream.

FIG. 5 is a flowchart that illustrates a method for determining whethera data stream is critical and assigning a channel to the data stream.

FIG. 6 is a flowchart that illustrates a method for assigning dedicatedchannels to critical data streams.

FIG. 7 is a flowchart that illustrates a method for assigning dedicatedchannels to critical data streams.

FIG. 8 is a flowchart that illustrates a method for assigning dedicatedchannels to critical data streams.

FIG. 9 is a flowchart that illustrates a method for terminate adedicated channel.

The drawing in which an element first appears is typically indicated bythe leftmost digit or digits in the corresponding reference number. Inthe drawings, like reference numbers may indicate identical orfunctionally similar elements.

DETAILED DESCRIPTION

As mentioned above, having a channel that is shared among different datasteams presents a risk that critical data may be bottlenecked bynon-critical data. To deal with this, embodiments disclosed heretransmit user's critical data streams on a dedicated channel. In oneexample, a network user, such as a web content provider, may send webcontent to its customers across the network. The web content may be sentin different data streams. Some of the data streams may be critical, andthe content provider may require dedicated channels with specificcapacities be assigned to this critical data.

The network user may be able to establish policies that define what datais and is not critical. Depending on the user policy, different types ofuser traffic may be assigned to different channels in the network withspecific capacities. Policies may specify what data is critical usingdifferent criteria. For example, the user may have a policy that anystream of data going to a given address, for example “salesforce.com,”is assigned a dedicated channel. While the description herein uses theterms “critical” and “non-critical” to describe the different datastreams sent on the different channels, a skilled artisan wouldrecognize that these apply to any data streams having different types.

In one embodiment, a user policy may allocate a single channel,sometimes referred to herein as a bundle channel, to handle all criticaltraffic, while keeping another, common channel for the non-criticaltraffic. In this embodiment, the critical data streams may compete witheach other over the capacity in their single dedicated channel. Inanother embodiment, the critical data may each be individually assigneda portion of the bundle channel. For example, if the bundle channel has50 Mbps bandwidth, each of its critical data streams may be allocated 5Mbps capacity. In this way, by allocating dedicated capacity to thecritical data streams, embodiments provide a user with a minimumcapacity available to its critical applications, regardless of its othernon-critical applications that use a common channel separate from thededicated channels.

The Detailed Description that follows is divided into five sections. Thefirst section describes, with respect to FIGS. 1A-B and 2, a network forestablishing connections for a user over a network. The second sectiondescribes, with respect to FIG. 3, allocating channels to user traffic.The third section describes, with respect to FIGS. 4-5, allocatingchannel to critical and common data streams of the user. The fourthsection describes, with respect to FIGS. 6-8, allocating capacity amongthe critical data streams of a user. The fifth section describes, withrespect to FIG. 9, terminating dedicated channels assigned to a user.

Network for Establishing User Connections

FIG. 1A illustrates a system 100 that includes a communication network108. The communication network 108 may be a local area network (LAN),metropolitan area network (MAN), or wide area network (WAN). It mayutilize any point-to-point or multipoint-to-multipoint networkingprotocols. The network access protocols used may include, for example,Multi Label Protocol Switching (MPLS), Ethernet, Asynchronous TransferMode (ATM), High-Level Data Link Control (HDLC), or Frame Relay.

Communication network 108 includes a plurality of routers, such asforwarding device 104, connected to a network user 102. Here, the term“forwarding device” refers to devices that switch or route packets,including devices at the data link layer (OSI layer 2) and the networklayer (OSI layer 3). Forwarding device 104 may be connected to user 102via a direct link, or indirectly over a local network. User 102 may bean individual or an enterprise network such as an organization'sinternal network. User 102 generates data traffic for differentdestinations on communication network 108. In embodiments user 102 maybe a web service provider, providing content to clients connected tonetwork 108.

Forwarding device 104 connects user 102 to network 108. Forwardingdevice 102 is connected to a policing device 106, in embodiments,policing device 106 keeps information about user policy on how to assignchannels to critical traffic. Using a policy created by the user,policing device 106 sends configuring signals to forwarding device 104.Based on the configuring signals, forwarding device 104 regulateschannel assignment to user 102 data streams, in other words, based ondecision by policing module 106, forwarding module 104 assigns adedicated channel to a user's critical data stream or assigns commonchannel to a non-critical data stream of the user.

The policies governing data streams generated by user 102 and destinedfor user 102 may be the same or different. In example embodiments, user102 may create a policy that only data streams generated by user 102 maybe critical. In other example embodiments, specific data streams to orfrom user 102 may be critical, but the with different channel capacityassignments in either direction.

For example, user 102 may create a policy such that all the data streamsgenerated by a subset of terminals of user 1 are critical. User 102 mayfurther specify in its policy that each critical data stream generatedby each terminal Should be assigned a dedicated channel capacity.Channel capacity for all the critical streams may be the same ordifferent. In another example, user 102 may create a policy in which asubset of its data streams are critical and the rest of its data streamsare not critical. The user may specify in its policy that thenon-critical traffic will share a common channel capacity.

FIG. 1B illustrates a system 100 b that provides connections overnetwork 108 to a user 102 b. According to an embodiment, user 102 b maygenerate data traffic from different terminals such as terminals 102 b1, . . . , 102 bN, connecting to a port 103 of a switch 107. Switch 107may be connected to a local area network (LAN) 109 that usestechnologies such as Ethernet or Token ring. Local area network 109 viaswitch 110 is connected to network 108 via router 112. In exampleembodiment shown in this figure, router 112 may regulate channelcapacities assigned to different data streams generated by user 102 b.In this embodiment policing device 106 is connected to router 112.

In other embodiments, switch 107 or switch 110 may regulate channelcapacities assigned to different data streams generated by user 102 b.In such embodiments, policing device 106 may be connected to therespective regulating switch.

Policing device 106 may determine whether a dedicated channel should beassigned to each stream of traffic from user 202. Policing device 106makes such determination based on a user-created policy. In anembodiment, policing device 106 sends a signal to router 112 toconfigure the router such that channel capacities are assigned tocritical traffic streams of user 102 b according to the user's policy.

FIG. 2 is a diagram that illustrates system 200 that shows forwardingdevice 104 and policing device 106 in greater detail. Forwarding device104 may include a forwarding module 210 and a regulating module 212.Forwarding module 210 receives packets in a data stream on an input tothe forwarding device. Forwarding module 210 further transmits thepackets to an output of the according to a destination address of thepackets.

Regulating module 112 regulates the capacity of a channel assigned to adata stream. For example, regulator 114 provisions the capacity fortransmitting a critical stream, according to a capacity for such streamspecified in the policy created by user 102.

In embodiments, policing device 106 includes a policy table 214 and apolicing module 216. Policy table 214 holds the policy information user102 has created for its data streams. For example, policy table 114 hasinformation indicating which types of data stream user 102 considers ascritical. For example user 102 may consider all data streams destined toa specific destination as critical. In another example where user 102includes multiple terminals, user 102 may consider all traffic generatedby certain terminals as critical. Other examples of critical datastreams include traffics generated during certain time periods that havecertain destination addresses. User 102 defines in its policy whatamount of capacity to be dedicated to each critical stream.

In an embodiment, the entire bandwidth available to user 102 may bedivided as shown in FIG. 3.

User Channel Allocation

FIG. 3 is a diagram illustrating an example channel capacity assignment300 to data streams of a user. To assign portions of the bandwidth toparticular channels, various techniques are available includingfrequency division multiplexing, code division multiplexing, timedivision multiplexing, or any other multiplexing schemes. Forillustration, frequency division multiplexing is shown in FIG. 3.

In FIG. 3, bandwidth 301 is available to all the data streams of user102. Common channel 302 is available to all non-critical traffic of theuser. In other words, all the non-critical traffic of user 102 sharechannel 302. Bundle channel 304 is assigned to all the critical trafficstreams of user 102. In one embodiment, all the critical traffic streamsshare bundle channel 304. Capacity sharing and channel accessalgorithms, such as Multiple Access with Collision Avoidance (MACA),Carrier sense multiple access (CSMA), or Distributed CoordinationFunction (DCF) may be used for carrying data on the common channel

In another embodiment, instead of having critical data streams share theentire bundle channel 304, dedicated channels within bundle channel 304may be assigned for each of the data streams. In particular, first andsecond dedicated channels 304 a and 304 b, which are part of the bundlechannel 304, are assigned to respective first and second critical datastreams of user 102.

In an example, 100 Mbps bandwidth may be available to all the datastreams of user 102. A channel with 10 Mbps bandwidth may be availableto all non-critical traffic of the user, and a bundle channel of 90 Mbpsmay be available to all the critical traffic streams of the user. Theuser may have 9 dedicated channels for 9 critical data streams whereeach channel has a 10 Mbps bandwidth. Alternatively, the user may have afirst dedicated channel with 40 Mbps bandwidth assigned to a firstcritical data stream, and a second dedicated channel with 60 Mbpsbandwidth assigned to a second critical data stream.

Channel Allocation to Critical and Common Data Streams

FIG. 4 is a flowchart that illustrates a method 400 for determining achannel for a data stream. Method 400 is described with respect to theexample embodiments in FIGS. 1A-B, 2, and 3.

Referring to FIG. 4, method 400 begins at step 402 by receiving a newdata stream. In an embodiment, the new data stream may be generated byuser 102. In another embodiment, the new data may be incoming anddestined to user 102. In embodiments, a forwarding device's forwardingmodule 210 illustrated in FIG. 2 receives the new data stream.

Each data stream may be one or more packets in time proximity with oneanother having a common (1) protocol, (2) source/destination InternetProtocol (IP) addresses, and (3) source/destination Transport ControlProtocol (TCP) or User Datagram Protocol (UDP) ports. When a certainamount of time passes after receipt of a packet having thesecharacteristics, a forwarding device determines that the flow has ended,and if the forwarding device receives any additional packets with thesecharacteristics, the forwarding device regards the packets as belongingto a new data stream.

Once a new data stream is received and identified, the forwarding devicedetermines whether the new data stream is critical to the user at step404. In embodiments the forwarding device's policing module 216 in FIG.2 determines whether the data stream is critical, using the user createdpolicy stored in a policy table 214.

When the data stream is critical, method 400 at step 408 assigns adedicated channel from bundle channel 304 to the data stream. Forexample method 400 may assign first dedicated channel 304 a to a firstcritical data stream of user 102. In some embodiments, regulator module112 assign the dedicated channel to the data stream, based on theconfiguring signal it receives from policing module 210.

When the data stream is not critical, method 400 at step 406 may assigncommon channel 302 to the data stream. In embodiments, regulating module212 assigns the common channel to the data stream.

FIG. 5 is a flowchart that illustrates a method 500 for determiningwhether a data stream is critical and determining a channel for the datastream. Method 500 is described with respect to the example embodimentsin FIGS. 1A-B, 2, and 3.

Referring to FIG. 5, method 500 begins by receiving the first packet ofa new data stream over common channel 302 from user 102 to forwardingdevice 104. In some embodiments, forwarding module 210 in the forwardingdevice 104 receives the first packet.

Method 500, at step 504, forwards the first packet of the data stream tothe destination over common channel 302. In embodiments, forwardingmodule 210, after receiving the first packet of a new data stream, willforward the first packet to the destination over common channel 302 thatbelongs to user 102.

At step 506 a copy of at least a portion of the data stream's firstpacket is forwarded to a policy device, such as policy device 106 inFIG. 2, and specifically policing device 106's policing module 216. Theportion of the packet may be a portion that includes information aboutthe packet, for example the header of the packet. In one example thefirst X number of bits of the packet may be forwarded onto the policingmodule.

At step 508, the policing module determines whether the first streamcontains critical data. In embodiments, the policing module uses theinformation in the copy of the portion of the packet to identify thedata stream. The policing module uses the user policy for the datastream stored in its policy table, to determine whether the data streamis critical according to the policy of the user.

To complete step 508, policing module may use the source or destinationaddress of the packet to identify the corresponding policy that user 102has created for the data stream. For example, if the user is created apolicy where all data streams destined to an address are critical, thenif the header information of the first packet indicates that the datastream is destined to the specified destination and the stream isidentified as critical.

When the data stream is determined to be critical at step 512, packetsof the data stream are forwarded over a dedicated channel to thedestination. To forward the packets, policing module 216 may send asignal to regulating module 212 in forwarding device 104, instructingregulating module 212 to assign a dedicated channel to the stream inaccordance with the specified policy of user 102.

When the data stream is determined not contain critical information, atstep 510, subsequent packets of the data stream continue to be forwardedover common channel 302 to the destination. For example, if the userdefines critical data streams based on destination address, when policymodule 216 determines that the destination address of the first packetin the data stream does not have any of the destinations user 102 hasdefined as critical, policy module 216 determines the data stream is notcritical. Subsequently, policy module 216 may send a signal toregulating module 212 of forwarding device 104 to send the remainingpackets of the data stream over common channel 302 to the destination.Common channel 302 may be shared among the user's non-critical data.

Allocating Capacity Among the Critical Data Streams

As discussed with reference to FIG. 5, when a data stream is determinedto contain critical data, a dedicated channel is assigned to it. Whencapacity is available in the dedicated channel, subsequent packets of acritical data stream are transmitted over the dedicated channel.Embodiments describe methods of transmitting packets of the criticaldata stream when capacity is unavailable over the dedicated channel.

FIG. 6 is a flowchart that illustrates a method 600 for assigningpackets to dedicated Channels. Again, method 600 is described withrespect to the example embodiments in FIGS. 1A-B, 2, and 3.

Referring to FIG. 6, method 600 starts at step 602 to assign bundlechannel 304 for transmitting all critical data streams of user 102. Inembodiments, policing module 216 reviews the user's policy to determinethe capacity of the bundle channel to be assigned to all critical datastreams of user 102. Policing module 216 may send a signal forconfiguring regulator module 212 to assign bundle channel 304 to allcritical data streams of user 102.

Method 600 determines at step 604 whether a data stream of user 102 iscritical. Embodiments described above with respect to FIG. 5 may be usedin determining whether the data stream is critical. When method 600determines that the data stream is not critical, method 600 ends in step616.

When the policing module determines that the data stream is critical, itsends a signal to the regulating module in the forwarding device,instructing regulating module to assign a dedicated channel within thebundle channel 304 to the data stream at step 606.

At step 608, the regulating module 212 determines whether there iscapacity available in the dedicated channel to a data stream fortransmitting a subsequent packet of the data stream. For example iffirst dedicated channel 304 a is assigned to the data stream, at step608 the regulating module 212 determines whether there is free capacityavailable on channel 304 b for forwarding a subsequent packet. Inembodiments, regulator module 212 determines whether there is freecapacity available for packets of a data stream using a dedicatedchannel. When free capacity is available on the dedicated channel,regulator module 212 sends the subsequent packet on the dedicatedchannel. In embodiments, regulator module 212 regulates sendingsubsequent packets of a critical data stream on the dedicated channelassigned to the data stream, when there is available capacity.

When regulator module 212 determines needed capacity is unavailable on adedicated channel for subsequent packets of the data stream, method 600transmits the packet on any free capacity in the bundle channel. Forexample, when there is no free capacity on a dedicated channel assignedto a critical data stream, any subsequent packet of the critical datastream will be transmitted using any available bandwidth, time slot, orcode word within the bundle channel. In embodiments, regulator module212 determines availability of free capacity for transmitting a packeton a dedicated channel and transmitting the packet on the bundle Channelwhen no free capacity is available on the dedicated channel assigned tothe data stream.

At step 612, method 600 assigns the packet a lower priority than anyother packet of any other critical data stream using the dedicatedchannel of the other data stream. In embodiments, regulator module 112assigns the lower priority to the packet.

FIG. 7 is a flowchart that illustrates a method 700 for assigningpackets to dedicated channels. Method 700 is described with respect tothe example embodiments in FIGS. 1A-B, 2, and 3.

Referring to FIG. 7, method 700 starts at step 702 by receiving a packetof a critical data stream. At step 704, method 700 determines whetherthere is free capacity available for the packet to be transmitted on thechannel dedicated to the data stream.

When capacity is available for the packet, method 700 at step 708forwards the packet on the dedicated channel. When no free capacity isavailable, method 700 at step 706 forwards the packet on common channel302 assigned to the user 102. In the embodiment shown in FIG. 2,regulating module 212 determines whether there is free capacityavailable for the packet on the dedicated channel. Regulating module 212may instruct the forwarding module 210 to forward the packet on thededicated channel when there is bandwidth available on the dedicatedchannel. When no free capacity is available on the dedicated channel forthe packet, regulator module 212 may instruct the forwarding module 210to forward the packet on the common channel 304 of user 102. Inembodiment, all the traffic forwarded on common channel 304 share thecapacity of the common channel.

FIG. 8 is a flowchart that illustrates a method 800 for assigningpackets to dedicated channels. Method 800 is described with respect tothe example embodiments in FIGS. 1A-B, 2, and 3.

Referring to FIG. 8, method 800 starts at step 802 by receiving a packetof a critical data stream. At step 804, method 800 determines Whetherthere is free capacity available for the packet to be transmitted on thechannel dedicated to the data stream.

When capacity is available for the packet, method 800 at step 806forwards the packet on the dedicated channel. When capacity isinsufficient for the packet, method 800 at step 806 drops the packet. Inembodiments, regulating module 212 determines whether there is freecapacity available for the packet on the dedicated channel. Regulatingmodule 212 may further instruct the forwarding module 210 to forward thepacket on the dedicated channel when there is bandwidth available on thededicated channel. When no free capacity is available on the dedicatedchannel for the packet, regulator module 112 may instruct forwardingmodule 110 to drop the packet.

Terminating Dedicated Channel Assignment

FIG. 9 is a flowchart that illustrates a method 900 for terminatingdedicated channel assignments. Method 900 is described with respect tothe example embodiments in FIGS. 1A-B, 2, and 3.

Referring to FIG. 9, method 900 starts at step 902 by determiningwhether a data stream is critical. Same approach as discussed above withrespect to FIG. 4 can be used for such determination. At step 904,method 900 determines whether a “finish” signal indicating the end ofthe data stream is received. In embodiments, regulator module 212determines whether a “finish” signal is received. At step 906 method 900determines whether there has been a new packet received in the datastream for a given time period. In embodiments, regulator module 212makes such determination.

When a “finish” signal has been received for the data stream or therehas not been a new packet received in the data stream for a given timeperiod, at step 908, method 900 terminates the dedicated channelassignment to the data stream. In embodiments, regulating module 212instructs forwarding module 104 to such this termination.

Another Example Embodiment

In an example embodiment a network content provider may generatecritical traffic for transmitting over the network to its users. Forexample a video content provider may generate video traffic for itsviewers and consider its traffic as critical. The content provider, inthis example, can create a policy that dedicated channels be assigned toall of traffic streams it generates. In this way, the content provideris enabled provide a service, for example video streaming service to itsclients, such that its data traffic will not share the same channels asthe rest of the traffic over the network.

CONCLUSION

The term “user,” as used herein, may encompass both a customer of thenetwork connectivity service, such as an employee of a business thatutilizes the network connectivity service, and a network administratorof the service provider itself. Users may also be at different companiesor organizations.

Policy table 214 may be any stored type of structured memory, includinga persistent memory. In examples, each database may be implemented as arelational database or file system.

Each of the servers and modules in FIG. 2 may be implemented inhardware, software, firmware, or any combination thereof.

Each of the servers and modules in FIG. 2 may be implemented on the sameor different computing devices. Such computing devices can include, butare not limited to, a personal computer, a mobile device such as amobile phone, workstation, embedded system, game console, television,set-top box, or any other computing device. Further, a computing devicecan include, but is not limited to, a device having a processor andmemory, including a non-transitory memory, for executing and storinginstructions. The memory may tangibly embody the data and programinstructions. Software may include one or more applications and anoperating system. Hardware can include, but is not limited to, aprocessor, a memory, and a graphical user interface display. Thecomputing device may also have multiple processors and multiple sharedor separate memory components. For example, the computing device may bea part of or the entirety of a clustered or distributed computingenvironment or server farm.

Identifiers, such as “(a),” “(b),” “(i),” “(ii),” etc., are sometimesused for different elements or steps. These identifiers are used forclarity and do not necessarily designate an order for the elements orsteps.

The present invention has been described above with the aid offunctional building blocks illustrating the implementation of specifiedfunctions and relationships thereof. The boundaries of these functionalbuilding blocks have been arbitrarily defined herein for the convenienceof the description. Alternate boundaries can be defined so long as thespecified functions and relationships thereof are appropriatelyperformed.

The foregoing description of the specific embodiments will so fullyreveal the general nature of the invention that others can, by applyingknowledge within the skill of the art, readily modify and/or adapt forvarious applications such specific embodiments, without undueexperimentation, without departing from the general concept of thepresent invention. Therefore, such adaptations and modifications areintended to be within the meaning and range of equivalents of thedisclosed embodiments, based on the teaching and guidance presentedherein. It is to be understood that the phraseology or terminologyherein is for the purpose of description and not of limitation, suchthat the terminology or phraseology of the present specification is tobe interpreted by the skilled artisan in light of the teachings andguidance.

The breadth and scope of the present invention should not be limited byany of the above-described exemplary embodiments, but should be definedonly in accordance with the following claims and their equivalents.

What is claimed is:
 1. A computer-implemented method for transmittingdata from a source to a destination through a plurality ofinterconnected forwarding devices, comprising: (a) receiving, at aforwarding device, on a common channel from the source to the forwardingdevice, a first packet in a first data stream, wherein the commonchannel has a common capacity; (b) forwarding, on the common channel,the first packet from the forwarding device to the destination; (c)determining whether the first data stream is a critical data streambased on information about the first packet in the first packet; (d)when the first stream is determined not to be critical in (c),configuring the forwarding device to forward a second packet of thefirst data stream on the common channel from the forwarding device tothe destination, wherein the common channel is shared with anothernon-critical data stream; and (e) when the first data stream isdetermined to be critical in (c), configuring the forwarding device toforward a second packet of the first data stream on a first channel fromthe forwarding device to the destination, wherein the first channel hasa first capacity, is dedicated to the first data stream and is differentfrom the common channel.
 2. The method of claim 1, further comprising:(f) determining whether capacity is available on the first channel forforwarding a third packet of the first data stream; (g) when the firstdata stream is determined to be critical in (c) and capacity isdetermined to be available in (f), configuring the forwarding device toforward, on the first channel, the third packet of the first stream fromthe forwarding device to the destination.
 3. The method of claim 2,further comprising: (h) when the first data stream is determined to becritical in (c) and free capacity determined to be unavailable in (f),configuring the forwarding device to forward on the common channel thethird packet of the first stream from the forwarding device to thedestination.
 4. The method of claim 2 wherein configuring in (e) furthercomprises when the first data stream is determined to be critical in (c)and capacity is determined to be unavailable in (f), configuring theforwarding device to drop the third packet.
 5. The method of claim 1,further comprising: forwarding, to a policing device, a copy of aportion of the first packet, wherein the portion includes theinformation about the first packet, and wherein determining (c) is bythe policing device using a policy defined by a user generating thefirst data stream.
 6. The method of claim 5, wherein the policycomprises using a source or a destination address of the first packet.7. The method of claim 5, further comprising: (f) receiving, at theforwarding device on the common channel from the source to theforwarding device, a first packet in a second data stream; (g)forwarding, on the common channel, the first packet from the forwardingdevice to the destination; (h) forwarding, to the policing device, acopy of a portion of the first packet, wherein the portion includesinformation about the first packet; (i) determining, by the policingdevice, based on the information in the portion of the first packet,whether the second data stream is another critical data stream; (j) whenthe second data stream is determined to be critical in (i), configuringthe forwarding device to forward on a second channel, a second packet ofthe second data stream from the forwarding device to the destination,wherein the second channel has a second capacity and is dedicated to thesecond data stream and is different from the common channel.
 8. Themethod of claim 7, further comprising assigning a bundle channel to allcritical data streams belonging to the user, wherein the bundle channelhas a bundle capacity that, when the first data stream is determinedcritical in (c), the bundle capacity comprises the first capacity of thefirst channel and, when the second data stream is determined critical in(i), the bundle capacity comprises the second bandwidth of the secondchannel.
 9. The method of claim 8, wherein configuring in (e) furthercomprises, when the first data stream is determined to be critical in(c) and when no free capacity is available in the first channel fortransmitting a third packet of the first data stream: (k) configuringthe forwarding device to transmit the third packet of the first datastream on free capacity in the bundle channel, and (l) when the seconddata stream is determined critical in (i) and the free capacity in (k)overlaps with the second capacity, assigning a lower priority to thethird packet of the first data stream than a packet of the second datastream.
 10. The method of claim 1, further comprising, when theforwarding device receives a finish message indicating end of the firststream, terminating the configuration of the forwarding device in (e) toforward any other packet of the first stream on the first channel. 11.The method of claim 1, further comprising: when the forwarding devicedoes not receive any packet belonging to the first stream for a periodof time, terminating the configuration of the forwarding device in (e)to forward any other packet of the first stream on the first channel.12. The method of claim 1, further comprising determining a price quotefor a user generating the first data stream based on the first capacityand an amount of time the first channel is used by the user.
 13. Asystem for transmitting data from a source to a destination through acommunication network, comprising: a forwarding device comprising aprocessor and a memory configured to receive on a common channel fromthe source to the forwarding device, a first packet in a first datastream, and to forward on the common channel, the first packet from theforwarding device to the destination, wherein the common channel has acommon capacity; and a policing device comprising a processor and amemory configured to: determine whether the first data stream is acritical data stream based on information about the first packet in thefirst packet; when the first data stream is determined not to becritical, configure the forwarding device to forward a second packet ofthe first data stream on the common channel from the forwarding deviceto the destination, wherein the common channel is shared with anothernon-critical data stream; and when the first data stream is determinedto be critical, configure the forwarding device to forward a secondpacket of the first data stream on a first channel from the forwardingdevice to the destination, wherein the first channel has a firstcapacity and is dedicated to the first data stream and is different fromthe common channel.
 14. The system of claim 13, wherein the forwardingdevice is further configured to determine whether capacity is availableon the first channel for forwarding a third packet of the first datastream, and the policing device is further configured to, when the firstdata stream is determined to be critical and capacity is determined tobe available by the forwarding device, configure the forwarding deviceto forward the third packet of the first stream on the first channelfrom the forwarding device to the destination.
 15. The system of claim14, wherein the policing device is further configured to: when the firstdata stream is determined to be critical and capacity is determined tobe unavailable, configure the forwarding device to forward the thirdpacket of the first stream on the common channel from the forwardingdevice to the destination.
 16. The system of claim 13, wherein thepolicing device is further configured to: when the first data stream isdetermined to be critical and capacity is determined to be unavailableon the first channel for transmitting a third packet of the firststream, configure the forwarding device to drop the third packet of thefirst stream.
 17. The system of claim 13, wherein the policing devicefurther comprises a policy table for storing a first policy defined by auser generating the first data stream for determining whether the firstdata stream is critical, and the policing device is further configuredto: receive a copy of a portion of the first packet, wherein the portionincludes information about the first packet; and configure theforwarding device to forward the second packet of the first stream usingthe policy in the first policy table.
 18. The system of claim 17,wherein the forwarding device is further configured to: receive, on thecommon channel from the source to the forwarding device, a first packetin a second data stream generated by the user; forward, on the commonchannel, the first packet to the destination; and forward to thepolicing device a copy of a portion of the first packet, wherein theportion includes information about the first packet; and the policingdevice is further configured to: determine, based on the information inthe portion of the first packet and the second policy, whether thesecond data stream is another critical data stream; and when the seconddata stream is determined to be critical, configuring the forwardingdevice to forward on a second channel, a second packet of the seconddata stream from the forwarding device to the destination, wherein thesecond channel has a second capacity and is dedicated to the second datastream and is different from the common channel; wherein the policytable further stores a second policy defined by the user for how toforward the second data stream.
 19. The system of claim 18, wherein theforwarding device is further configured to: assign a bundle channel toall critical data streams belonging to the user, wherein the bundlechannel has a bundle capacity that comprises the first capacity of thefirst channel when the first data stream is determined critical, andcomprises the second capacity of the second channel when the second datastream is determined critical.
 20. The system of claim 19, wherein thepolicing device is further configured to, when the first data stream isdetermined to be critical and if no free capacity is available in thefirst channel for transmitting a third packet of the first data stream,configure the forwarding device to transmit the third packet of thefirst data stream on free capacity in the bundle channel, and the theforwarding device is further configured to, when the second data streamis determined critical and the free capacity in the bundle channeloverlaps with the second capacity, assign a lower priority to the thirdpacket of the first data stream than a packet of the second data stream.21. A program storage device tangibly embodying a program ofinstructions executable by at least one machine to perform a method fortransmitting data from a source to a destination through a plurality ofinterconnected forwarding devices, the network including a plurality ofinterconnected switching devices, the method comprising: (a) receiving,at a forwarding device, on a common channel from the source to theforwarding device, a first packet in a first data stream, wherein thecommon channel has a common bandwidth; (b) forwarding, on the commonchannel, the first packet from the forwarding device to the destination;(c) forwarding, to a policing device, a copy of a portion of the firstpacket, wherein the portion includes the information about the firstpacket; (d) determining whether the first data stream is a critical datastream based on the information about the first packet in the firstpacket and a policy defined by a user generating the first data stream;(e) when the first stream is determined not to be critical in (d),configuring the forwarding device to forward a second packet of thefirst data stream on the common channel from the forwarding device tothe destination, wherein the common channel is shared with anothernon-critical data stream; and (f) when the first data stream isdetermined to be critical in (c), configuring the forwarding device toforward a second packet of the first data stream on a first channel fromthe forwarding device to the destination, wherein the first channel hasa first bandwidth dedicated to the first data stream and is differentfrom the common channel.
 22. A computer-implemented method fortransmitting data from a source to a destination through a plurality ofinterconnected forwarding devices, comprising: (a) receiving, at aforwarding device, on a common channel from the source to the forwardingdevice, a first packet in a first data stream, wherein the commonchannel has a common capacity; (b) forwarding, on the common channel,the first packet from the forwarding device to the destination; (c)determining whether the first data stream has a particular type based oninformation about the first packet in the first packet; (d) when thefirst stream is determined not to have the particular type in (c),configuring the forwarding device to forward a second packet of thefirst data stream on the common channel from the forwarding device tothe destination, wherein the common channel is shared with another datastream not having the particular type; and (e) when the first datastream is determined to have the particular type in (c), configuring theforwarding device to forward a second packet of the first data stream ona first channel from the forwarding device to the destination, whereinthe first channel has a first capacity dedicated to the first datastream and the first channel is different from the common channel.